You have to use this script for the "position" controller, otherwise it won't work (I'm almost sure that's the problem... Maybe you want to use the "infinite rotation" script from the same page, that's the one you should use for "orientation"...)

I'll try that out Kubajzz, thanks.I can't use the infinite rotation, I'm trying to circle a camera about an object, not rotate it about a point.For the time being I did it by hand which looks fine, but it'll still be nice to figure out how to use the script again.

Edit:That did work Kubajzz, thanks. At first I was confused at what you meant which took me a while to reply, but suddenly it dawned on me. I had been using the 'fov' controller instead of the position controller.Thanks